THYRIDIDAE OF AFRICA AND ITS ISLANDS n 



in different species. Two anal veins are invariably present and the main variation 

 found in the hind wings is in the relative positions of Sc + R 1 and Rs. In a few 

 species these veins join for a short part of their length, usually about half way along, 

 but they are alway separate at the base and wing margin. In the majority of species 

 these two veins start separately, and while they may approach closely, do not join 

 together. The frenulum hook (retinaculum) under the fore wing is conspicuous 

 in the males as a sclerotized hook and is very prominent in some species. The hook 

 is absent from the females. The males have a single frenulum bristle and the 

 females usually three bristles. In only one genus (Sinecalca) is the frenulum absent 

 in both sexes. 



Abdomen. The abdominal segments present fewer external characters than in 

 some families of Lepidoptera. In some species the pattern is of use for specific 

 determinations and in a few species the sternite of the last abdominal segment of 

 the male is slightly modified (Text-figs 9-14), but these modifications are always 

 slight and never approach those found in some other families, e. g. Drepanidae 

 (Watson, 1965, Wilkinson, 1967). All species are without tympanal organs in the 

 abdomen. 



Genitalia. The genitalia of both sexes show little intra-specific variation and are 

 used to supplement the characters in the external morphology in determining the 



10 



11 



12 



13 



Figs 9—14. Eighth abdominal sternite, <J. 9. Striglina eguttalis Gaede; 10. Striglina 

 strigifera Strand; 11. Striglina ferula sp. n.; 12. Striglina trepida sp. n.; 13. Striglina 

 augescere sp. n. ; 14. Striglina guttistigma Hampson. 



